Summary: Existing methods for European and American option pricing under the variance Gamma (VG) model are quite complex and time consuming in calculation. Thus, an efficient and accurate Willow tree method is proposed in this paper. Johnson curve is used to construct the asset price nodes in the VG process and the FFT-COS method is used to calculate the transfer probability between asset price nodes. Besides, the theoretical convergence of the Willow tree method for European options is analyzed. Moreover, some numerical experiments are conducted to demonstrate the efficiency and accuracy of the proposed method.